Tony Cornell, of the Society for Psychical Research, says the number of spooky sightings started to decline with the introduction of mobiles 15 years ago.

The Cambridge expert explained: 'Sightings have remained consistent for centuries. Until three years ago we'd receive reports of two new ghosts every week.'

Steve Parsons, of the Wirral's Parascience Society, agrees there has been a dramatic fall in the number of ghosts reported.

But he reckons it's all down to a lack of TV programmes like The X-Files rather than mobile phone microwaves in the atmosphere.

He said: 'In the run-up to the year 2000 there was loads of stuff on the telly about the paranormal and that made the public more aware.

'But now people may have an experience and not realise that it's of a paranormal nature. And, anyway, we use lots of hi-tech equipment in our research and that has no effect. Good solid reliable ghosts are there and they are as hard as ever to catch.'